To provide a log house which is excellent in durability and design, and can be efficiently built.

Both side surfaces of a log material 11 form a protruding curved surface, and a notch 12 is vertically, horizontally notched to form a square notch part 13 and a round notch part 14. In the square notch part 13, the upper and lower surfaces, and right and left surfaces of a notched core part are formed respectively so as to be parallel to each other. The round notch part 14 is notched so as to widen toward the lower end of the log material 11 and become flush with the side surface of the square notch part 13, and fitted to the side surfaces forming the protruding curved surfaces of the log materials 11, 11 vertically intersecting and overlapping each other.